{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-50194: Steeltoe vulnerable to management-port isolation bypass via spoofed Host header","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-50194","status":"final","version":"1","initial_release_date":"2026-06-17T21:03:26.756Z","current_release_date":"2026-06-17T21:03:26.756Z","revision_history":[{"date":"2026-06-17T21:03:26.756Z","number":"1","summary":"Initial machine-readable export from HarborGuard."}]},"distribution":{"tlp":{"label":"WHITE"},"text":"Public CVE data; freely redistributable."},"notes":[{"category":"description","text":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. When Steeltoe management endpoints versions 3.2.2 through 3.3.0 and 4.1.0 are configured to listen on an alternate port (`Management:Endpoints:Port` is configured), the middleware responsible for restricting access to the endpoints uses the `Host` HTTP header rather than the actual network socket port. Versions 3.4.0 and 4.2.0 patch the issue. If an immediate upgrade to a patched version is not possible, add explicit ASP.NET Core authorization (`RequireAuthorization`) to all sensitive actuator endpoints as a defense-in-depth measure independent of port isolation and/or configure the reverse proxy or load balancer to enforce the `Host` header value and prevent clients from setting an arbitrary port.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-50194 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-50194"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-50194"},{"category":"external","summary":"https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-58f6-6rj2-3v8r","url":"https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-58f6-6rj2-3v8r"},{"category":"external","summary":"https://github.com/SteeltoeOSS/Steeltoe/commit/4cbc352fe89ac2e6c609554e435ab28996fec5e9","url":"https://github.com/SteeltoeOSS/Steeltoe/commit/4cbc352fe89ac2e6c609554e435ab28996fec5e9"},{"category":"external","summary":"https://github.com/SteeltoeOSS/Steeltoe/commit/b7ca93c510aaa08d7e4ebec40ce20c5811c2c4b6","url":"https://github.com/SteeltoeOSS/Steeltoe/commit/b7ca93c510aaa08d7e4ebec40ce20c5811c2c4b6"}]},"product_tree":{"branches":[{"category":"vendor","name":"SteeltoeOSS","branches":[{"category":"product_name","name":"Steeltoe.Management.Endpoint","branches":[{"category":"product_version","name":"< 4.2.0","product":{"name":"SteeltoeOSS Steeltoe.Management.Endpoint < 4.2.0","product_id":"CSAFPID-1","product_identification_helper":{"cpe":"cpe:2.3:a:steeltoeoss:steeltoe.management.endpoint:\\<_4.2.0:*:*:*:*:*:*:*"}}}]}]},{"category":"vendor","name":"SteeltoeOSS","branches":[{"category":"product_name","name":"Steeltoe.Management.EndpointCore","branches":[{"category":"product_version","name":">= 3.2.2, < 3.4.0","product":{"name":"SteeltoeOSS Steeltoe.Management.EndpointCore >= 3.2.2, < 3.4.0","product_id":"CSAFPID-2","product_identification_helper":{"cpe":"cpe:2.3:a:steeltoeoss:steeltoe.management.endpointcore:\\>\\=_3.2.2\\,_\\<_3.4.0:*:*:*:*:*:*:*"}}}]}]}]},"vulnerabilities":[{"cve":"CVE-2026-50194","title":"Steeltoe vulnerable to management-port isolation bypass via spoofed Host header","notes":[{"category":"description","text":"Steeltoe is an open source project that provides a collection of libraries that helps users build cloud-native applications. When Steeltoe management endpoints versions 3.2.2 through 3.3.0 and 4.1.0 are configured to listen on an alternate port (`Management:Endpoints:Port` is configured), the middleware responsible for restricting access to the endpoints uses the `Host` HTTP header rather than the actual network socket port. Versions 3.4.0 and 4.2.0 patch the issue. If an immediate upgrade to a patched version is not possible, add explicit ASP.NET Core authorization (`RequireAuthorization`) to all sensitive actuator endpoints as a defense-in-depth measure independent of port isolation and/or configure the reverse proxy or load balancer to enforce the `Host` header value and prevent clients from setting an arbitrary port.","title":"CVE description"}],"product_status":{"known_affected":["CSAFPID-1","CSAFPID-2"]},"scores":[{"cvss_v3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N","baseScore":8.2,"baseSeverity":"HIGH"},"products":["CSAFPID-1","CSAFPID-2"]}],"remediations":[{"category":"none_available","details":"No fixed version is published yet. Monitor the upstream advisory.","product_ids":["CSAFPID-1","CSAFPID-2"]}]}]}